互隔交链孢酚致DNA聚合酶β基因突变的实验研究

Study on the Mutation of DNA Polymerase β Affected by Alternariol

目的观察互隔交链孢酚对NIH/3T3细胞中DNA聚合酶β(DNApolβ)基因突变的影响,研究互隔交链孢酚致癌可能的机制。方法NIH/3T3细胞分为两组:①各正常细胞组;②AOH组,AOH浓度为8μmol·L-1。用RTPCR方法从细胞全RNA中扩增出DNA聚合酶β基因cDNA序列,应用TA克隆技术,克隆至pGEMTeasy载体后进行测序,分析序列变化。结果测序后发现正常组DNA聚合酶β基因序列无任何变化,AOH组中228位点发生TC突变(导致39号氨基酸由Tyr变为His),319位点也有TC突变(导致69号氨基酸由IIe变为Thr)。结论AOH可导致NIH/3T3细胞中的DNA聚合酶β发生点突变,推测AOH的致癌作用可能与引发细胞中DNA聚合酶β基因突变有关。

Objective To observe the mutation of DNA polymerase β (DNApol β)in NIH/3T3 cell line affected by alternariol(AOH),and study the mechanism of alternariol inducing cancer.[WTHZ]Methods The cells were affected by AOH,and divided into 2 groups:①normal cells;②AOH8 μmol/L.DNApol β gene was amplified through RT-PCR from the cells,then cloned with pGEM-T easy vector and sequenced.[WTHZ]Results The sequence of normal group was normal,but there was 2 point mutations in another group.[WTHZ]Conclusion AOH can induce point mutation of DNApol β gene.The mechanism of AOH inducing cancer relates to the mutation of DNApol β gene affected by AOH.